Explosion decoupling (isolation)
The above (damping and relief) systems reduce explosion effects to a safe level, thus protecting the plant against destruction. Nevertheless, residual explosion effects in the form of a wave of fire and pressure may spread through a system of pipes, ducts and conveyor transfers to neighbouring facilities.
This phenomenon leads to generation of secondary explosions which bring about much worse effects. In extreme cases, this may lead to a complete destruction of process plants. To counteract this phenomenon – in compliance with the Polish and European law – explosion decoupling (cut-off) systems must be applied. It is aimed at closing physically the pipelines, ducts and conveyor transfers that connect the explosion-affected facility with the remaining parts of the plant.
Application: explosion protection of equipment units (including silos, filters, cyclones, mixers, drying plants, pelleting machines, etc.) in presence of flammables at explosive concentrations levels. The HRD cylinders provide explosion protection for processing equipment units, vessels, and ductwork which contain class ST1 to ST3 particulate matter, gases and/or hybrid mixtures in all industrial sectors.
ATEX-certified rotary valves (also known as rotary dispensers) are applied as feeding dispensers for bulk products and airflow-reduction gates in dust extraction systems, central vacuum cleaning systems, pneumatic handling systems, and in similar applications. If certified for compliance with ATEX 95, the rotary valves are approved for use in Ex-zones and as standalone explosion isolation systems.
The VENTEX explosion isolation valves are available in a wide variety of sizes and versions for passive explosion isolation. The valve is intended for installation in the ductwork of dust extraction / separating systems, positive or negative pressure handling systems, drying systems, or granulation systems. In most cases, the valves are resistant to the maximum explosion pressure.
While being a rather unusual solution, this explosion isolation system provides two unique features. First, the explosion isolation valve can be triggered to close by a decompression panel opening system (in the explosion venting system) or a dedicated IR sensor. Second, the explosion isolation valve can be reset for repeated use after an explosion.
A pressure rotary lock is a system of two rotary valves interconnected by a pressurization chamber. The pressure rotary locks enable pressure-less feeding or discharge of powders or liquids to or from positive-pressure or vacuum-pressure areas. If ATEX 95 certified, the pressure rotary locks can be operated in Ex-zones or as standalone explosion isolation systems.
Scope of works
- Selection of an optimum decoupling system;
- Delivery and installation (of mechanical and electrical components);
- Inspection and servicing.